Burner for liquid fuel



Aug. 13, 1940. c s 2,211,059

BURNER FOR LIQUID FUEL Filed May 19, 1957 INVENTOR. CHARLES A. HAAsATTORNEY.

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Patented Aug. 13, 1940 .UNITED STATES PATENT OFFICE 4 Claims.

My invention is an improved construction of burner for liquid fuel, forexample, heavy petroleum oil, and includes a burner casing provided witha mixing chamber into which the liquid fuel 1 tube supplying additionalair to the mixture for burning, in which tube the burning of the mixtureis begun.

As a result of supplying the liquid fuel and air independently, andindependently projecting the liquid fuel and air into the mixing chamberas described, I find I am able to produce a more perfect mixture thanwhere the velocity of the flowing stream of air is dependent upon thefuel flow into and through the burner, and furthermore, as a result ofthe particular manner in which the fuel and air are projected into themixing chamber, I am able to completely break up the liquid fuel intoextremely minute particles which are thoroughly blended and mixed wtihthe air projected into the mixing chamber, and as a result a fuel andair mixture is produced which is in ideal condition to be burned. Inaddition, by projecting the perfectly mixed and blended fuel particlesand air at high velocity through a minute orifice in the delivery jet ornozzle into the Venturi tube with additional air in properlyproportioned amount to effect perfect and complete combustion of thefuel without the presence of excess air, a hotter fiame results and agreater amount of heat is produced from a given quantity of liquid fuel,than I have been able to produce from the same quantity of the sameliquid fuel in any other way.

I have found by actual test that there are several constructions ofburners embodying my invention referred to, which will effectivelyoperate to produce the results described, which are adapted fordifferent uses, and I illustrate in the present application thepreferred construction which I have found to be particularly effectivein carrying out my invention.

My invention will be best understood by reference to the accompanyingdrawing illustrating the improvements thereof, in which:

Fig. 1 shows my burner construction in vertical, longitudinal, sectionalview, and

Fig. 2 is a horizontal, sectional view to an enlarged scale, of theconstruction shown in 'Fig. 1, taken along the line 2-4.

Similar numerals refer to similar parts throughout the several views.

In Figs. 1 and 2, I illustrate, my burner construction, which may besupplied with liquid fuel. and air under pressure in any desired mannerknown to the art. The burner consists of a block of metal in which acentral bore 6| is formed, which constitutes the mixing chamber of theburner, the air supply pipe 56a being connected with a tight fit intothe outer end of said bore. The bore 6| extends nearly through the blockof the burner 60, where it terminates in a 5 delivery opening 62 ofsmall size, so that the heated mixture of atomized fuel and air may beprojected into the Venturi tube 63 and there burned. The bore 6| of theburner 60 is crossed by a transverse bore of smaller diameter contain-20 ing with a snug fit, a fuel tube 64 having tightly closed ends, theouter end of said tube being sealed in the block of the burner 60 toprevent leakage, in any desired manner, for example, by brazing. Theblock of the burner 60 contains a small diameter bore substantiallyparallel with the bore 6| and extending through the side wall of thefuel tube 64, the outer end of which bore 65 is tightly connected withthe end of the fuel supply pipe 49a. The fuel tube 64 is provided withopposite apertures 64a and 64b, which are of small size andsubstantially iii the axis of the bore 6]. As a result of theconstruction described, by supplying liquid fuel and air to the pipes49a and 5611 under pressure and in any suitable manner, the liquid fueland air are highly heated by the heated condition of the block of theburner 60 resulting from the action of the fiame produced, and the flowof air under pressure from the pipe 56a into the mixing chamber 6|, pro-5; duces eddy currents as illustrated in Fig. 2, around the fuel tube64, into which eddy currents the heated liquid fuel is projected throughthe small openings 64a and 64b, with the result that the fuel iseffectively broken up and atomized, and thoroughly blended and mixedwith the heated air in the niixing chamber'fil, so that practically aperfect fuel mixture is projected at high velocity through the outletopening 62 for burning in the Venturi tube 63. With this construction,the Venturi tube 63 is provided at its base with a flange 63asubstantially parallel with the face of the block of the burner 60, andsaid flange is secured to said block by bolts 66, tubular separators 61being placed on the bolts between the flange and the block, to permitthe air to enter into the smaller end of the Venturl tube 63, betweenthe tubular separators 81. This construction operates efiiciently, dueto the smaller end of the Venturi tube 63 being open to the atmospherearound the burner 60, so that the production of eddy currents in theVenturi tube 83 around the outlet opening 62, is impossible. The flange63a is spaced such a distance from the block of the burner 60, that theair required for complete combustion with maximum fuel consumption forwhich the burner is designed, will readily flow into the smaller end ofthe Venturi tube 63, without admitting excess air that would cool thecombustible gases and interfere with efficient heat production.

In using the burners described, I find air pressures of from four totwelve pounds per square inch are effective in preparing heavy fuel oilfor practically perfect burning, depending upon the burner constructionand upon the amount of heat it is required to produce. The flameproduced with a discharge orifice of from one thirtysecond of an inch toone-sixteenth of an inch in diameter, can readily be varied from alength of about one foot to four feet or more by varying the pressureson the air and fuel oil supplied to the burner,

The fuel oil employed with the burners described, can be as heavy asnumber oil with entirely satisfactory results, referring to the systemof numbering fuel oils commonly in use by which the oils designated bylower number are lighter and contain different proportions of volatileconstituents, the number 4 011 containing little of such volatileconstituents, the number 5 oil being a heavy, opaque oil containingpractically no readily volatile elements, and the number 6 oil, theheaviest in the series, being practically a solid at freezingtemperatures. The heavier oils contain more heat units per unit volumethan the lighter oils, which in part accounts for the large heatproduction made possible by the burner construction above described.

While I have shown my invention in the particular embodiment abovedescribed, I do not limit myself thereto as I may employ equivalentsthereof without departing from the scope of the appended claims.

What I claim is:

1. In a liquid fuel burner, the combination of a metallic body portionhaving a first cylindrical bore constituting a mixing chamber, one endof said bore being adapted to receive air under pressure and the otherend of said bore having a small discharge opening of mixture-atomizingsize, said body portion having a second cylindrical bore ofsubstantially smaller diameter than said first bore and with its axisextending transversely across said first bore, whereby said second borecomprises end portions extending from opposite sides of said first bore,and a metal tube tightly fitting the end portions of said second boreand crossing said first bore, said tube having closed ends and havingalso a liquidatomizing discharge opening in said first bore, said bodyportion having a. third bore for receiving liquid fuel and extending ina direction crossing said second bore, said third bore being continuedthrough a side wall of said tube between the closed ends of the latter.

2. In a liquid fuel burner, the combination of a metallic body portionhaving a first cylindrical bore constituting a mixing chamber, one end osaid bore being adapted to receive air under pressure and the other endof said bore having a small discharge opening of mixture-atomizing size,said body portion having a second cylindrical bore of substantiallysmaller diameter than said first bore and with its axis extendingtransversely across said first bore, whereby said second bore comprisesend from opposite sides of said first bore, and a metal tube tightlyfitting the end portions of. said second bore and crossing said firstbore, said tube having closed ends and having also a liquidatomizingdischarge opening in said first bore. said body portion having a thirdbore for receiving liquid fuel and extending in a direction crossingsaid second bore, said third bore being continued througha side wall ofsaid tube between the closed ends of the latter, the discharge openingof said first bore being cylindrical and having a diameter of the orderof from one thirtysecond to' one-sixteenth of an inch.

3. In a liquid fuel burner, the combination of a metallic body portionhaving a first cylindrical bore constituting a mixing chamber, one endof said bore being adapted to receive air under pressure and the otherend of said bore having a small discharge opening of mixture-atomizingsire, said body portion having a second cylindrical bore ofsubstantially smaller diameter than said first bore and with its axisextending transversely across said first bore, whereby said second borecomprises end portions extending from opposite sides of said first bore,and a metal tube tightly fitting the end portions of said second boreand crossing said first bore, said tube having closed ends and havingalso two oppositely disposed liquid-atomizing discharge openings ofcylindrical form in said first bore, said body portion having a thirdbore for receiving liquid fuel and extending in a direction crossingsaid second bore, said third bore being continued through a side wall ofsaid tube between the closed ends of the latter, the oppositely disposeddischarge openings in said tube being substantially coaxial with saidfirst bore.

4. In a liquid fuel burner, the combination of a metallic body portionhaving a first cylindrical bore constituting a mixing chamber, one endof said bore being adapted to receive air under pressure and the otherend of said bore having a small discharge opening of mixture-atomizingsize, said body portion having a second cylindrical bore ofsubstantially smaller diameter than said first bore and with its axisextending transversely across said first bore, whereby said second borecomprises end portions extending from opposite sides of said first bore,and a metal tube tightly fitting the end portions ofsaid second bore andcrossing said first bore, said tube having closed ends and having alsotwo oppositely disposed liquid-atomizing discharge openings ofcylindrical form in said first bore, said body portion having a thirdbore for receiving liquid fuel and ex-- tending in a direction crossingsaid second bore, said third bore being continued through a side wall ofsaid tube between the closed ends of the latter, the oppositely disposeddischarge openings in said tube being substantially coaxial with saidfirst bore, the discharge opening of said first bore being cylindricaland having a diameter of the order of from one thirty-second toone-sixteenth of an inch.

CHARLES A. HAAS.

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